Selected SPI Neck Finish Specifications

Standard dimensions derived from GPI/SPI 400 Series, 410 Series and 415 Series Tables.

 

A container's neck finish holds the closure with protruding threads. A container and its corresponding cap must have matching finishes. For example, a 24/410 bottle will only accept a 24/410 closure.

 

Screw thread or continuous thread closure sizes are expressed with two numbers separated by a hyphen or slash. The first number refers to the millimeter diameter measured across the inside of the cap's opening or the outside of the bottle's threads. The second number refers to the thread style, "GPI" or "SPI" finish. The Glass Packaging Institute (GPI) and Society of the Plastics Industry (SPI) are responsible for establishing uniform standards for glass and plastic container neck finishes. The closure industry does not necessarily adhere to the same standards, so it is best practice to purchase containers and caps from the same supplier when possible.

 

 

MM	T		E		400H		410H		415H		S		I	THDS/ IN.
	Max	Min	Max	Min	Max	Min	Max	Min	Max	Min	Max	Min	Min
20	19.89	19.48	17.75	17.35	9.08	9.04	14.45	13.69	19.23	18.46	1.32	0.56	10.26	8
24	23.87	23.47	21.74	21.34	10.54	9.78	16.79	16.03	24.69	23.93	1.55	0.79	13.10	8
28	27.64	27.12	25.25	24.74	10.47	9.78	18.36	17.06	27.86	27.10	1.55	0.79	15.60	6
33	32.14	31.52	29.74	29.14	10.62	9.86			33.00	32.00	1.55	0.79	20.10	6
38	37.50	36.88	35.10	34.50	10.62	9.86					1.55	0.79	17.45	6
40	40.13	39.37	37.75	36.00	10.62	9.86					1.55	0.79	27.70	6
43	42.00	41.25	39.62	38.86	10.62	9.86					1.55	0.79	29.60	6
48	47.50	46.74	45.11	44.35	10.62	9.86					1.55	0.79	35.10	6
51	50.00	49.10	47.60	46.71	10.75	10.00					1.55	0.79	37.60	6
53	52.50	51.61	50.11	49.23	10.75	10.00					1.55	0.79	40.10	6
58	56.50	55.60	54.10	53.22	10.75	10.00					1.55	0.79	44.10	6
60	59.50	58.60	57.10	56.21	10.75	10.00					1.55	0.79	47.00	6
63	62.51	61.62	60.12	59.23	10.75	10.00					1.55	0.79	50.00	6
70	69.50	68.60	67.00	66.22	10.75	10.00					1.55	0.79	57.00	6
75	74.00	73.10	71.60	70.71	10.75	10.00					1.55	0.79	61.50	6
77	77.10	76.20	74.70	73.81	12.75	12.00					1.90	1.14	64.70	6
83	83.00	82.12	80.00	79.07	12.75	12.00					1.90	1.14	70.00	5
89	89.18	88.30	86.12	85.24	14.00	13.20					1.90	1.14	74.10	5
100	100.0	99.10	96.95	96.00	15.55	14.80					1.90	1.14	85.00	5
110	110.0	109.1	107.0	106.0	15.55	14.80					1.90	1.14	95.00	5
120	120.0	119.1	117.0	116.0	17.80	17.00					1.90	1.14	105.0	5

All dimensions in mm and converted from original SPI tables. This table is a guide only for more information please refer to Glass Packaging Institute/ Society of the Plastics Industry.

 

Common GPI / SPI Neck Finishes - for Series 400-410-415 neck finishes.

 

1 Thread turn -- 1.5 Thread turns -- 2 Thread turns

 

 

“H” Dimension: The height of the neck finish. Measured from the top of the neck to the point where the diameter, “T”, extends down and intersects the shoulder.
“S” Dimension: Measured from the top of the finish to the top edge of the first thread. The “S” dimension is the key factor in determining the orientation of the closure to the bottle and the amount of thread engagement between the bottle and cap.
“I” Dimension: The inner diameter of the bottle neck. Specifications require a minimum “I” to allow sufficient clearance for filling tubes. Liner less closures, with a plug or land seal, and dispensing plugs and fitments require a controlled “I” for a proper fit.
“T” Dimension: The outside diameter of the thread. The tolerance of the “T” dimension determines the mate between bottle and closure.
“E” Dimension: The minor diameter measured across the root of the threads.